Wheelchair Mobility Performance enhancement by

changing wheelchair properties; what is the effect of

grip, seat height and mass?

Rienk van der Slikke, Annemarie de Witte, Monique Berger, Daan Bregman, Dirk Jan Veeger

IntroductionWheelchair configuration and performance

Performance in wheelchair sports

• Athlete – wheelchair• One functional unit

• Individual athletes• Class / athlete bound performance goals• Sport / field position bound performance goals

• Wheelchair mobility performance• Optimize wheelchair settings / configuration

Environment

WheelchairMobility

Performance

Model by Kees van Breukelen

MethodsWheelchair Mobility Performance Monitor

Wheelchair basketball field testNormal wheelchair setup and five altered settings

Wheelchair Mobility Performance Monitor

• Key wheelchair kinematics measured with IMUs

Average

Forw

ard

Rota

tiona

l

Acceleration

Acceleration

Van der Slikke, R. M. A., Berger, M. A. M., Bregman, D. J. J., & Veeger, H. E. J. (2016). From big data to rich data: the key features of athlete wheelchair mobility performance. Journal of biomechanics, 49(14), 3340-3346.

Wheelchair basketball field test

1.6m

12 m3.8m

• Straight sprint – interval• Curves - interval• Turn on the spot – interval• Without / with ball• Combined

van der Slikke, R. M., Bregman, D. J., Berger, M. A., De Witte, A. M., & Veeger, D. J. H. E. (2018). The future of classification in wheelchair sports: can data science and technological advancement offer an alternative point of view?. International journal of sports physiology and performance, 13(6), 742-749.

Test conditions: changes in wheelchair setup

Seat heightLow (L) -7.5%

High (H)+ 7.5%

Added massMass Central (MC)+ 7.5%

Mass Distributed (MD)+ 3.75% & + 3.75%

KG

KGKG

Neutral (N) Grip (G)

Outcomes

• Number of outcomes• Six WMPM outcomes complete test per test condition• Four outcomes per test part (n=14) and per test condition• Seven comparisons

• Effect size (ES)• Differences expressed in ES

• Small |0.2| < |0.5|• Moderate |0.5| < |0.8|• Large > |0.8|

• Number of ES > 0.2

Results & conclusionsWheelchair Mobility Performance

Outcome level effect sizesConclusions

Wheelchair settings

Linear1 avg. speed (m/s)2 ! avg. best speeds (m/s)3 avg. acceleration 2m (m/s2)Rotational4 avg. rotational speed in curve (⁰/s)5 ! avg. best rot. speed in turn (⁰/s)6 avg. rot. acceleration (⁰/s2)

Linear

Rotational

1.84

1.94 m/s

2.41

2.6 m/s

1.6 m/s2

1.38

271

364 o/s2

206 o/s

183

Neutral

Low

High

Weight Central

Weight Distr.

Grip

!

!

69 o/s

62

1

2

3

4

5

6

KG

KGKG

Outcome level

• Outcomes• 4 main outcomes• 14 test parts• 6 WMP outcomes• 7 comparisons• 434 outcomes

• Effect size• Small |0.2| < |0.5|• Moderate |0.5| < |0.8|• Large > |0.8|

Comb.

WMP Ove

rall

Variable Regu

lar

Ball

Inte

rval

Righ

t

Left

R ba

ll

L ba

ll

R In

terv

al

L in

terv

al

Righ

t

Left

R in

terv

al

L in

terv

al

Regu

lar

12m curve Turn on the spot12m straight

Avg 0.17

ard

SpBest 2 -0.09 Abs max 0.21 -0.05 -0.04 -0.10 0.25 0.18 0.08 -0.02 0.14 -0.04 -0.18 -0.20 0.38 0.00

Neutral - Acc 2m Avg 0.02 Abs avg -0.07 0.13 -0.05 -0.07 0.10 -0.07 -0.13 0.07 0.08 -0.08 0.09 -0.03 -0.29 0.01Forw

a Sp

Low Curve Avg -0.07on SpTurn best 2 0.02 Abs max -0.43 -0.57 0.26 -0.46 -0.07 -0.20 0.05 0.10 -0.20 0.18 0.03 0.05 -0.27 0.14

Acc Avg 0.05 Abs avg -0.33 -0.16 -0.13 -0.04 -0.01 -0.19 -0.14 0.10 -0.10 0.24 0.04 0.08 -0.10 0.09Rota

tio Sp

Avg -0.13

ard

SpBest 2 -0.11 Abs max 0.17 -0.09 -0.26 -0.17 -0.02 -0.09 -0.04 -0.09 0.01 0.34 0.23 0.19 0.09 -0.10

Neutral - Acc 2m Avg 0.07 Abs avg -0.25 0.26 -0.01 -0.29 0.11 -0.15 -0.14 0.07 0.07 -0.24 -0.16 -0.19 -0.34 -0.10Forw

a Sp

High Curve Avg -0.27on SpTurn best 2 -0.30 Abs max -0.15 -0.36 0.01 -0.22 -0.13 0.11 -0.06 -0.20 -0.17 -0.22 -0.11 -0.20 -0.48 -0.24

Acc Avg -0.13 Abs avg -0.45 -0.17 -0.13 0.03 0.14 -0.10 -0.12 0.09 -0.15 -0.22 -0.11 -0.34 -0.29 -0.03Rota

tio Sp

Avg -0.35rd SpBest 2 -0.11 Abs max -0.17 -0.03 -0.16 -0.06 -0.14 -0.27 -0.05 -0.09 -0.16 0.47 0.35 0.41 -0.27 -0.09

Low - Acc 2m Avg 0.00 Abs avg -0.19 0.11 0.02 -0.25 0.03 -0.02 0.00 -0.04 0.00 -0.11 -0.15 -0.10 -0.13 -0.11Forw

a Sp

High Curve Avg -0.25on SpTurn best 2 -0.27 Abs max 0.19 0.00 -0.12 0.20 0.00 0.06 -0.04 -0.28 0.13 -0.38 -0.14 -0.23 -0.26 -0.30

Acc Avg -0.15 Abs avg -0.05 -0.05 -0.01 0.04 0.20 0.09 0.01 0.02 -0.03 -0.39 -0.18 -0.39 -0.19 -0.12Rota

tio Sp

Avg 0.03

ard

SpBest 2 -0.01 Abs max -0.04 -0.21 -0.09 -0.37 -0.22 -0.32 -0.05 0.04 -0.07 0.17 -0.36 0.14 0.30 -0.03

Neutral - Acc 2m Avg 0.02 Abs avg -0.36 -0.13 -0.30 -0.45 -0.51 -0.42 -0.45 -0.26 -0.23 -0.49 -0.69 -0.37 -0.49 -0.45Forw

a Sp

Weight Curve Avg -0.32on SpCentral Turn best 2 -0.22 Abs max 0.02 -0.63 -0.15 -0.19 -0.11 0.09 -0.16 -0.24 -0.14 0.01 -0.13 0.00 -0.21 -0.39

Acc Avg -0.05 Abs avg -0.19 -0.14 -0.24 0.04 -0.01 -0.09 -0.06 0.03 -0.03 -0.01 -0.03 -0.10 -0.07 0.02Rota

tio Sp

Avg 0.13rd SpBest 2 -0.09 Abs max 0.01 -0.15 -0.05 -0.03 -0.11 -0.18 0.00 0.03 0.06 0.18 0.36 0.02 0.18 -0.20

Neutral - Acc 2m Avg 0.01 Abs avg -0.32 -0.17 -0.28 -0.52 -0.43 -0.34 -0.41 -0.15 -0.34 -0.39 -0.37 -0.39 -0.59 -0.36Forw

a Sp

Weight Curve Avg -0.21on SpDistributed Turn best 2 -0.26 Abs max -0.54 -1.12 -0.31 -0.63 -0.75 -0.52 -0.45 -0.18 -0.48 -0.27 -0.39 -0.31 -0.41 -0.43

Acc Avg -0.32 Abs avg -0.40 -0.44 -0.38 -0.53 -0.36 -0.45 -0.43 -0.21 -0.59 -0.29 -0.31 -0.36 -0.35 -0.29Rota

tio Sp

Avg 0.17rd SpWeight Best 2 0.01 Abs max 0.09 0.05 0.05 0.36 0.19 0.18 0.03 0.06 0.14 0.21 0.51 0.02 -0.10 -0.21Central - Acc 2m Avg 0.06 Abs avg 0.14 -0.01 0.04 -0.06 0.07 0.07 0.05 0.16 -0.07 0.18 0.41 -0.01 -0.24 0.07Fo

rwa Sp

Weight Curve Avg 0.02on SpDistributed Turn best 2 -0.04 Abs max -0.69 -0.57 -0.25 -0.49 -0.49 -0.41 -0.24 0.04 -0.34 -0.26 -0.23 -0.35 -0.30 -0.11

Acc Avg -0.29 Abs avg -0.21 -0.48 -0.23 -0.48 -0.33 -0.42 -0.40 -0.25 -0.58 -0.30 -0.22 -0.27 -0.27 -0.34Rota

tio Sp

Avg -0.10

ard

SpBest 2 -0.16 Abs max -0.01 -0.12 -0.13 0.30 0.31 0.16 -0.20 0.07 0.18 0.12 -0.09 -0.08 0.32 0.02

Neutral - Acc 2m Avg -0.08 Abs avg -0.14 0.13 0.02 -0.04 0.09 -0.07 -0.17 0.07 0.11 0.04 -0.04 -0.01 -0.08 -0.01Forw

a Sp

Grip Curve Avg -0.15on SpTurn best 2 -0.28 Abs max -0.21 -0.61 0.08 -0.13 -0.04 -0.12 -0.06 0.12 -0.12 0.01 0.05 0.00 -0.27 0.07

Acc Avg -0.07 Abs avg -0.18 -0.18 -0.14 0.05 -0.06 -0.11 -0.11 0.07 -0.10 -0.04 -0.02 -0.21 -0.20 0.24Rota

tio Sp

Test parts (n=14)

Out

com

es

Com

paris

ons (

n=7)

Seat height

• Minimal effect on speed• Hardly effect on acceleration• Most effect on rotational

speed• Minimal effect rotational

acceleration

Normal - LowNormal - High

Low - High

25%19%

38%

7% 33%7%

44% 56%50%

13%27%

20%

Percentage of Effect Sizes > 0.2

Rotational AccRotational SpeedForward AccForward Speed

Added mass

• Minimal effect on speed• Clear effect on acceleration

• No difference between location

• Clear effect on rotational speed in distributed mass

• Very clear effect on rotational accelerationin distributedmass Normal - Mass

Central Normal - MassDistributed Mass Central -

MassDistributed

38%13%

25%

87%

80%

13%

38%94%

75%

7%

100%

100%

Percentage of Effect Sizes > 0.2

Rotational AccRotational SpeedForward AccForward Speed

Conclusions settings

• Seat height• High, (rotational) performance ↓

• Mass central • Acceleration ↓

• Mass distributed• Acceleration ↓• Rotational speed & acceleration↓

• Grip• Hardly effect

Percentage of Effect Sizes > 0.2

Rotational Acc

Rotational Speed

Forward Acc

Forward Speed

Seat height

Added mass Grip

Perspective

• WMPM method & fieldtest• Sensitive to small changes in wheelchair

configuration

• Structural WMPM monitoring• Evaluate training effect• Optimize wheelchair configuration

Out of the lab, onto the court

Wheelchair Mobility Performance quantified

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